https://en.wikipedia.org/wiki/Special:MassMessage
Permission error
From Wikipedia, the free encyclopedia
You do not have permission to send a message to multiple users at once, for the following reason:
The action you have requested is limited to users in one of the groups: Administrators, Mass message senders.
This feels a bit obtuse and the options for customizing the error message seem limited.
Version: unspecified
Severity: normal
URL: https://en.wikipedia.org/wiki/Special:MassMessage